revert(shell): move iris integration to the iris branch

Reverts 43dfe48, 0692ae3, e0cdcd6 and the cable-description half of
098da70 (the star-prompt stats stay). master returns to the pre-iris
shell setup: atuin in fish/zsh/bash, the down -> pj binding with
PJ_QUIET, and the fish/zsh key bindings as they were. The iris work
lives on the `iris` branch.

dot_config/fish/functions/_pj_bind.fish

@@ -1,13 +1,14 @@
-function _pj_bind --description 'ctrl-p: pj (tv --inline), then redraw the prompt in the right place'
+function _pj_bind --description 'ctrl-p / down: pj (tv --inline), then redraw the prompt in the right place'
     # pj reports through $PJ_STATE: `open` = the picker was cancelled and
     # left the cursor on the line below the prompt; empty = no task sources,
     # nothing drawn — but fish's repaint after an external command still
     # lands one line low, so both step back up. `ran` = a task printed
     # output: new line, prompt below it.
     set -lx PJ_STATE (mktemp)
-    _iris_busy start
+    if contains -- --quiet $argv
+        set -lx PJ_QUIET 1
+    end
     pj
-    _iris_busy stop
     set -l state (cat $PJ_STATE)
     switch "$state"
         case open ''